The present disclosure relates, in various exemplary embodiments, to electronic devices and materials suitable for use in such devices. More specifically, the present disclosure relates to electronic devices that incorporate a multilayer dielectric.
Thin film transistors are fundamental components in modern-age electronics, including, for example, sensor, imaging, and display devices. Thin film transistor circuits using current mainstream silicon technology may be too costly, particularly for large-area device applications such as backplane switching circuits for displays like active matrix liquid crystal monitors or televisions, where high switching speeds are not essential. The high costs of silicon-based thin film transistor circuits are primarily due to the capital-intensive fabrication facilities and the complex high-temperature, high-vacuum photolithographic fabrication processes under strictly controlled environments.
Because of the cost and complexity of fabricating silicon-based thin film transistor circuits using conventional photolithography processes, there has been an increased interest in plastic thin film transistors which can potentially be fabricated using liquid-based patterning and deposition techniques, such as spin coating, solution casting, dip coating, stencil/screen printing, flexography, gravure, offset printing, ink jet-printing, micro-contact printing, and the like, or a combination of these processes. Such processes are generally simpler and more cost effective compared to the complex photolithographic processes used in fabricating silicon-based thin film transistor circuits for electronic devices. To fabricate liquid-processed thin film transistor circuits, liquid processable materials are therefore required.
Most of the current materials research and development activities for plastic thin film transistors has been devoted to semiconductor materials, particularly liquid-processable organic and polymer semiconductors. On the other hand, other material components such as dielectric materials have not been receiving much attention.
In embodiments, it is desirable for the materials for the dielectric to have a number of attributes including for example the following: (1) a good electrical insulating property; and (2) compatibility with the semiconductor materials. An issue with conventional gate dielectrics is that it may be difficult to accommodate all the desired attributes for the dielectric materials. Accommodating the desired attributes (1) and (2) is accomplished by embodiments of the present invention.
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